Duplex combination extension lathe



Feb. 25, 1947. R. D. CAVANAGH v DUPLEX COMBINATION EXTENSION LATHE FiledApril 20, 1944 3 Sheets-Sheet l V .D. aavaiza gk INVENTOR.

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Feb. 25, 1947; R. D, CAYANAGH 2,416,612

DUPLEX COMBINATION EXTENSIC JN LATHE Filed April 20,-1'944 5Sheets-Sheet 2 Cavarza gh INVENTOR.

HTTORIVEVJ'.

Feb.'25, 1947- R. D. CAVANAGH DUPLEX COMBINATION EXTENSION LATHE FiledApril 20, 1944 5 Sheets-Sheet 3 I N VEN TOR.

D. Caz

. "bers l'lIl are-held' by V projecting, transverse flanges of the angle=mem-- Patented Feb. 25, 1947 DUPLEX COMBINATION EXTENSION LATHE Rex D.Cavanagh, Bloomington, 111. assignor of twenty-five per cent to RobertNord-Fagerburg,

Bloomington, 111.

Application April20, 1944, Serial No. 531,927

'3 Claims.

'Ihedevice forming thesubject matter of this application is a lathe, andone object of the invention is to provide novel means whereby the lathemay be adapted readily and quickly to cut threads of diiferent pitches.

vAnother object of the invention is to provide npyel means whereby thecombined longitudinal andcross feed slide may be actuated by hand or bpower, at'the will of an operator.

' A further object of the invention is to improve the headstock and thetailstock, and to bring about improvements in the combined cross feedand'longitudinal feed slide.

Aiurther object of the invention is to provide anovelshiftablecarriageymovable on a bed, and

carryinga tailstock and a combined cross feed and longitudinal feed, formovement relatively to each other and relatively to a headstock andassociated parts mounted on the bed.

It is within the province of the disclosure to improve generally and toenhance the utility of devices of that type to which the presentinvention appertains.

,With the above and other objects in view, which will appear; as thedescription proceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it beingunderstood that changes-in the preciseemiment of the invention herein disclosed, may

be made within the scope of what 'is claimed,

without departing from the ho in the accompanying drawings:

Fig. 1 shows-in vertical longitudinal section, a lathe constructed inaccordance with the inven tion, parts remaining in elevation;

;Fig. 2 is a longitudinal section taken approximately on line 2-2vof'liigure 1, parts being broken away;

3 is a section on the line 3-'3 of-Fig.

Fig. 4'iS a section on theline 4-4 of Fig.

5 is a section on Fig. 6 is a section on the line -5 of Fig.

Figs? is asecti'on-o-n the line l-'! of Fig. 1;

Fig. 8 is a vertical transverse section taken through the means wherebythe combined cross feed and longitudinal feed mechanism may be coupledoperatively with the feed screw.

In carryingout the invention, there is provided a'bed -l, comprising achannel I00, the cross 'sectionoi -which is shown in Fig. 5. On theouter, lateral surfaces of'the channel I00, angle'memscrews 102. Theinwardly spirit of the inven- 1 l the lined-5 of Fig l 1 carriage 2(Fig. his

"dc-r109, engagedzby a.

bersi 0| cooperate with the side walls of the channel H10, to defineguidew'ays 103. I The transverse flanges of the angle members I'M aresupplied with holding devices; which may be set screws 104.

The numeral 2 designates a carriage,'adjustable longitudinally of thebed I. Upon the carriage 2 is mounted a tailstock, a longitudinal andcross feed mechanism, and an adjustable, all-angle, tool-holding viseall to be dealt with specifically hereinafter.

The carriage 2 embodies longitudinal side rails 3 and transverse endmembers 4', shown in Fig. 1. Figure 5 discloses that the lower portionsof the side rails 3 of the carriage 2 have outstanding flanges M5,received for reciprocation in the guideways H33. Since-the carriage 2maybe adjusted longitudinallyof-the bed I, the lathe is well adapted toreceive work of different lengths, grossly considered; although thelathe embodies means which renders frequent adjustments of the Vcarriage on the bed unnecessary. The set screws I0 4, which are carriedby the inwardly projecting flanges of the angle members 181, 'may beadvanced to bear uponthe flanges H15 of the carriage 2, and, thus,thecarriage may be secured in adjusted positions longitudinally of-thebed l, which forms part of the supporting structure. At their upperedges, the side rails il -of the carriage 2 are supplied with inwardextended flanges l6, appearing-in Figs. 5 and 7. 1

A channel-shaped slideror base plate It (Fig. '7) receives the upperportion of the carriage 2, and to the slide, the tailstock lili-issecured, as indicated at H16; Below the flanges 16 of the disposed aclamp plate 11. A vertical shaft Iii is journaled in one side portion ofthe tailstock I4 and is held against downward'movement by a collar-I08thereon. The shaft 18 is threaded at I01 into the clamp plate [1, and ismanipulated'by ahand wheel 19, or equivalent, device. a

The structure last above described constitutes means wherebythetailstock M may beheld fixedly'in any position to which itmay havebeen adjusted longitudinally of the carriage 2.

The tailstock l4 terminates at its upper end in a tubular bearing '20,wherein a tail spindle 2| is 'removably mounted. The tail spindle 2| ismanipulated by a crank 26 orthe like, the tail spindle having atransverse, circumscribing shouling '20 by a set screw cap 23, 'held onthe bearj H0 or th like. The tail spindle 2| is threaded foadvancement-androtraction, as indieatedlat 25; into an opening lineatedin Fig. 8.

. opening 4|,

a horizontal shaft 42, journaled in the guide 38 i (Fig. 1), in which aed for reciprocatory adjustment at tality of a feed screw 35, mounted toithe slide 21, but held against longitudinal movement therein, the feeding handle 36. through a depen II I'.

.strumentality of the 'c the half-nut 40 may be lowered, into'engagementfeed screw 5, however, m

in the cap 23. A renewable and interchangeable center point 22 isthreaded or held otherwise in the inner end of the tail spindle 2I.

A slide 21 has adjustment longitudinally of the carriage 2 and is heldthereon, for such adjustment, by any appropriate or conventional means,designated by the reference character The slid 21 is provided with atransverse track 28, to which is secured a vertical'guide 38, best de-A,plate 39 is mounted for reciprocation in the guide 38. The plate 39may be referred to as a carrier, since it carries, at its, 1 1 lowerend, a trough-lik e, internally threaded member or half-nut 4.0. V

The plate or carrier 39 is provided with an wherein operates aneccentric 43 on and actuated by a handle 44.

The construction of the mechanism last above 3 described is such thatthe plate or carrier 38 and the half-nut 46 downwardly, at the may bemoved upwardly or will of an operator, for a 3 purpose to be set forthhereinafter.

The slide 21 has oppositely disposed grooves 29 cross feed slide I I Iis mountthe will of an operator, the aforesaid adjustment beingcommunicated to the slide through the instrumenrotate on screw having anoperat- The feed screw 35 is threaded ding lug 34 on the cross feedslide The cross feed slide III includes an upstanding pedestal 38,wherein a tool post 3| is mounted for adjustment about a vertical axis,the numeral 32 designating any appropriate means or holding the toolpost against rotation, and for retaining a tool 33 in operative relationto the work 31-al1 as well understood by those skilled in the art. Aheadstock 6 is secured at II 2 to the bed I, and upon the headstock issecured a tubular head I0, in which are located anti-friction bearingsII4, wherein is journaled a head spindle I I. The bearings II4, whetherof the ball or roller type, reduce the coefficient 'of friction underall speeds, prevent premature side play and wear, and serve as thrustbearings. The head spindle II carries a chuck I2, of such constructionas the nature of the work may demand, the removable and'renewable centerpoint or. mandrel of the head spindle being designated by the numeralI3. A washer H3 or the like, on the head spindle II, overlaps andretains the innermost antifriction bearing H4, and is retained by thechuck I2.

Speed-change pulleys 64 and-65 are secured to the head spindle II, andit is from them that the head spindlereceives rotation immediately, thework between the centers I3 and 22 being rotated relatively to the tool33 of Fig. 5.

It is shown in Fig. 1 that a feed screw is mounted for rotation in theend plates 4 of the, carriage 2, the feed screw being retained againstlongitudinal movement therein; Through the inarrier or plate 39 of .Fig.8,

with the feed screw 5. Theslide 21 and parts carried thereby then may-beadjusted longitudinally of the carriage 2, by hand, since the feed screwis equipped with means 66 whereby rotation may be imparted to itmanually. The

ay acquire rotation from r will next be set forth.

A set screw or the like, indicated at II5, holds in the end of the feedscrew 5, a shaft 8 of polygonal cross section, the feed screw having asocket 1 for the reception of one end of the shaft. The shaft 8 may beconsidered as part of the feed screw 5. A sleeve 8' rotates with theshaft 8 and, in turn, is mounted to rotate in the headstock 6. The hub59 of a gear 9 is secured to the sleeve 8'. The shaft 5 is received inthe sleeve 8'.

An arm 58 is mounted to swing at the will of an operator on the hub 59of the gear 9. A 1 pinion 51 and a gear 56 are mounted at II6 (Fig. 4)to rotate as one piece on the arm 58. When the arm 58 is swung to theleft in Fig. 4, the pinion 51 comes into mesh with the gear 9 and thegear 56 comes into mesh with a gear wheel 55 mounted to rotate on thehead spindle II.

Under such circumstances there is provided a power driven mechanism forrotating the feed screw II and for moving the slide 21 longitudinally ofthe'carriage 2, that mechanism comprising one of the pulleys 64-65, thehead spindle II, the gear 55, the gear 56, the pinion 51 and the gear 9.

Any suitable means may be provided for holding the armin position to theleft of that which the arm occupies in Fig. 4, the gear 56 being in meshwith the gear 55, and the pinion 51 being in mesh with the gear 9.Having that end in view, a bellcrank lever 60 is fulcrumed at II1 on thearm 58, the bellcrank lever including a handle 6| and a cam 62, the cambeing adapted to be engaged with a shoulder 63 on the headstock 6.

When it is desired to employ the lathe for thread cutting, the mechanismof Fig. 8 is actuated to disengage the half-nut 46 from the feed screw5, motion being imparted to the slide 21,

0 longitudinally of the carriage 2, by an instrumentality best shown inFig. 2 and embodying details which appear in Figs. 3, 4 and 5.

The headstock 6 carries a lateral bracket 45, wherein a tubular shaft 46is journaled for, rotation. A head IIS and a set collar II9 on the shaft46 cooperate with the bracket 45, to prevent longitudinal movement ofthe shaft.

Rotation is imparted to the shaft 46 by way of a sprocket wheel 52thereon, the head spindle II carrying a sprocket wheel 53, the sprocketwheels being connected operatively by a sprocket chain 54. V

The slide 21 is equipped with a lateral oifset .49 removably andinterchangeably held, 'by means of a set screw 5I. A feed screw 48 isthreaded through the nut 55. The feed screw is provided with a foot I28,held in the bore of the hollow shaft 46, and more specifically in thepart II8, by a set screw 41 or the like. 7

The sprocket wheel 53, the head spindle II, the sprocket chain 54 andthe sprocket wheel 52, constitute means for rotating the shaft 46 andthe feed screw 48, the feed screw functioning to advance the slide 21along the carriage 2. By

loosening the set screws 41 and 5I, the feed screw 48 and the nut 55 maybe removed, a pair of corresponding elements being substituted therefor,the'threading thereof being such as to 7 advance the slide 21accordingly, to cut, by means of the tool 33 of Fig. 5, a thread havinga pitch differing from the pitch resulting from theoperation of theparts which have been removed. 'I'he carriage 2 may be held in adjustedpositions, longitudinally of the bed I,

, provided with a socket, wherein a nut 581s by set screws I04. Thestructure shown in Fig. 8 raises the half-nut 40 out of engagement withthe feed screw 5 and lowers the half-nut into engagement with the feedscrew. The tailstock I4 is held in adjusted positions, longitudinally ofthe carriage 2, by way of the shaft 18 of Fig. 7 and attendant parts.Ihe feed screw 35 of Fig. 5 brings about a cross feed of the slide I l land parts which it carries. When thread cutting is not to be carriedout, the slide 21 is moved longitudinally of the carriage 2 by screw 5,the shaft 8 and parts shown in Fig. 3, which connect the shaftoperatively with the head spindle ll. When screw cutting is to becarried on, the half-nut 40 may be disengaged from the screw 5 and,then, the sprocket chain structure of Fig. 3 actuates the screw 48. Aninterchange of the members 50 and 48 be made, to cut threads ofdifferent pitches.

I claim:

1. A lathe comprising a bed, a headstock mounted on the bed, a channeledcarriage having flanges, a tailstock mounted for sliding movement on theflanges and longitudinally of the carriage, a clamp plate in thecarriage and movable under the flanges with the tailstock, meansextending above the carriage and carried by the tailstock for actuatingthe plate to clamp the flanges between the plate and the tailstock, acombined cross feed and longitudinal feed mechanism, means for mountingsaid mechanism on the carriage for movement longitudinally of the bed,means for mounting the carriage on the bed for free sliding movementtoward and away from the headstock under push or pull imparted directlyto the carriage by an operator, thereby to secure a rapid and grossadjustment of said mechanism longitudinally of the bed, means mounted onthe carriage and cooperating with said mechanism to secure a slow andfine adjustment thereof, longitudinally of the bed, and a releasableholding device cooperating with the carriage and the bed to secure thecarriage in fixed positions longitudinally of the bed.

2. A lathe comprising a longitudinally channeled bed having guidewaysextending longitudinally therein, a longitudinally channeled carriageset in the guideways and slidable longitudinally thereof into and out ofthe bed, means for clamping the carriage in the guideways, a headstockmounted within one end of the chantioned for engagement with the feedscrew,

neled bed and secured thereto, a tailstock slidably mounted on thecarriage, means for clamping the tailstock to the carriage, separatehandoperated and power-driven feed screws, a shaft detachably connectedto one of the feed screws, power mechanism operatively connected to saidshaft and to the other feed screw, said shaft being detachable from itsfeed screw to permit actuation of said feed screw independently of thepower mechanism, a slide mounted on the carriage and separate means onthe slide for operative engagement with the respective feed screws, oneof said means being mounted for movement into and out of engagement withits feed screw.

3. In a lathe, the combination with a bed, a carriage slidably mountedin the bed and movable into and out of one end thereof, and means forsecuring the carriage against movement, of a tailstock on the carriage,a feed screw swiveled in the carriage, a slide mounted on the carriage,tool-holding means on the slide and means cooperating with the feedscrew for coupling the slide to the screw, said means including a nutguide carried by the slide, a plate slidably mounted in the guide andextending below the guide and into the carriage, a half nut on the slideposisaid plate having an opening, an eccentric rotatably mountedrelative to opening and means for actuating the eccentric to shift theplate and move the half nut into or out of engagement wit the feedscrew.

REX D. CAVANAGH.

REFERENCES CITED 4 The following references are of record in the file ofthis patent:

UNITED STATES PATENTS the guide and seated in the I

